1. Field of the Invention
Example embodiments of the present invention relate to laser lithography, patterning apparatuses and methods for the same.
2. Description of the Conventional Art
Spatial light modulation with optical micro-electro-mechanical-system (MEMS) devices may provide parallel writing in conventional UV-lithography. A conventional spatial light modulator (SLM) chip may include, for example, dynamic random access memory (DRAM) CMOS circuitry with several million individually addressable pixels on top. The pixels may be deflected by a difference in electrostatic force between a mirror element and an address electrode. In one example, a pattern generator using an SLM may have a smaller field stop for exposing a series of images of the SLM. A workpiece may be arranged on a stage, which may move, for example, in a continuous, substantially continuous, stepwise, or substantially stepwise, manner. An electromagnetic radiation source (e.g., pulsed electromagnetic radiation source, such as, a pulsed laser, a flash lamp, a flash from a synchrotron light source, etc.) flashes to freeze an image of the SLM on the workpiece. The SLM may be reprogrammed with a different pattern before each flash such that a contiguous image may be composed on the workpiece.
Conventional integrated circuit manufacturing techniques may use a number of masks or reticles (e.g., greater than 30) including a pattern of a layer in the integrated circuit. These conventional masks or reticles may be manufactured in a lithographical manner using, for example, electron beams or laser beams for exposing a layer of material sensitive to the type of beam chosen. The mask material may be transmissive and a thin layer of opaque material may be attached on one side. In the thin material the pattern of a layer of the integrated circuit may be created. The mask may have, for example, pattern N times larger than the pattern to be printed on the semiconducting substrate for forming the integrated circuit. The reduction in size may be performed in a stepper, which uses the mask(s) for forming the integrated circuit.
Conventional direct-writers may be based on electron beams (e.g., shaped beams), in which the pattern may be assembled from flashes, each of which may define a geometrical figure. Other conventional systems may use raster scanning of Gaussian beams. Conventional mask writers, which use beams of electrons or laser beams for forming the pattern on a workpiece, may use lower scanning speeds and may scan in one dimension.
Other conventional SLM writers disclosed, for example, in U.S. Pat. No. 6,717,097 and U.S. Patent Publication No. 2003/0160980, the entire contents of both of which are incorporated herein by reference, may produce a pattern (e.g., a bitmap pattern), for example, by printing an entire frame of a pattern in one flash.
A conventional spatial light modulator (SLM) may include a number of modulator elements, which may be set in a way to such that a pattern may be formed. Conventional SLMs may be exposed to any type of electromagnetic radiation, for example, deep ultra violet (DUV) or extreme ultra violet (EUV) for forming the pattern on the mask or any other workpiece.